My dehumidifier is designed to handle low temperatures. I had this one for 6 years. Recently, I noticed that the humidity reading is stuck at 20. The temp in the room is around 55. I tried unplugging it and plugging it back in. Nothing changed. The motor still works. The filter is clean and the coils look clean as well. Any solution?

Dehumidifiers - Fedders - A7DH45B2A Dehumidifier